In recent years, study on organic compounds of germanium (a homologue of carbon) has actively been conducted, and many study results have been presented or published. Thus, attention is being paid to organogermanium compounds in various fields, particularly medical and pharmaceutical fields.
For example, it is reported that carboxyethylgermanium sesquioxide (Japanese Patent Publication No. 2498/1971) which is an organogermanium compound formed by bonding of a propionic acid derivative of germanium and oxygen atom at a 2:3 ratio shows a hypotensive action to spontaneous hypertensive rats, an amyloidosis-alleviating action, a macrophages and NK cells-augmenting action, an interferon-inducing action, an antitumor action, etc. The above sesquioxide is in trial use clinically.
The above carboxyethylgermanium sesquioxide is represented by the following basic chemical formula. EQU (Ge--C--C--COOH).sub.2 O.sub.3
If in the above formula an amino group is introduced at the .alpha.-position of the carboxyl group --COOH to obtain a compound represented by the following chemical formula, ##STR7## this compound can be viewed as an amino acid.
It is well known that amino acid is a generic name for compounds represented by the following chemical formula ##STR8## and exists in every creature as its essential component. The importance of amino acid lies in that a plurality of amino acids bond to each other to form various proteins and further in that amino acids are metabolized in living body in various ways to become precursors for other substances which are important to living body.
Accordingly, if an amino group could be introduced, as an additional structure, into the above mentioned carboxyethylgermanium sesquioxide which is already found to have excellent pharmacological actions, the resulting organogermanium compound is highly expected to find novel utility.